Well, a coworker recently rigged up eleven's api to a coffee machine sensor. It now sings, loudly, an original composition to the effect of "make a new pot you asshole" whenever it gets low. We've gotten country, symphonic metal, southern hip hop, smooth british singing, accusatory broadway musical, 20's-style jazz singer, and more - it's different every time.

While the advisability of this particular project is up for debate, I do think it's something that could only exist with an API like eleven's.